Dignified

Try reseating the RAM and remove the hard drive. If still no display, you may be looking at a bad motherboard or a fault with the integrated graphics. In the case of the motherboard, it would need to be repaired or replaced. If it's the integrated graphics, the CPU would have to be replaced (if yours is the FCPGA type of CPU - if it's the BGA flavor, then it's back to the motherboard needing serviced or replaced).